{
  "$type": "site.standard.document",
  "description": "A degradation state estimation apparatus estimates a degradation state of a battery energy storage system including a secondary battery and a DC-AC converter. The apparatus includes an estimation arithmetic processing unit (27) that estimates an open circuit voltage (V)and an internal resistance…",
  "path": "/patents/1436065",
  "publishedAt": "2026-07-01T00:00:00.000Z",
  "site": "at://did:plc:oql6ds5vnff4ugar6rruliwd/site.standard.publication/3mn3ohu7oxx5w",
  "tags": [
    "G01R31/00",
    "DAIWA CAN CO LTD [JP]"
  ],
  "textContent": "A degradation state estimation apparatus estimates a degradation state of a battery energy storage system including a secondary battery and a DC-AC converter. The apparatus includes an estimation arithmetic processing unit (27) that estimates an open circuit voltage (V)and an internal resistance (R) with respect to a charging rate of the secondary battery based on a charge-discharge voltage (V)and a charge-discharge current (I) of the secondary battery, and input-output power of the DC-AC converter, estimates efficiency (η) of the DC-AC converter and power consumption (E) of an auxiliary device of the DC-AC converter, and estimates charge-discharge energy efficiency (RTE) with respect to the charging rate of the secondary battery and a rated input-output ratio on an AC side of the DC-AC converter based on the estimated open circuit voltage, the internal resistance, the efficiency of the DC-AC converter, and the power consumption of the auxiliary device of the DC-AC converter.",
  "title": "DETERIORATION STATE ESTIMATION DEVICE FOR POWER STORAGE SYSTEM, DETERIORATION STATE ESTIMATION METHOD, AND POWER STORAGE SYSTEM OPERATION OPTIMIZATION METHOD"
}